Spark control for internal combustion engines



1, 1935- J. R. PRICE 2,016,023

SPARK CONTROL FOR INTERNAL COMBUSTION ENGINES Filed Nov. 8, 1935 2 Sheets-Sheet l Get. 1, 1935.

J. R. PRICE 2,016,023

SPARK CONTROL FOR INTERNAL COMBUSTION ENGINES Filed Nov. 8, 1933 2 Sheets-Sheet 2 lllllllllllllllllllll lllllllllllli.

Patented Oct. 1, 1935 SPARK CONTROL FOR INTERNAL COMBUS- TION ENGINES John Ralph Price, Charlottesville, Va.; Hilda Price Jarvis administratrix of said John Ralph Price, deceased Application November 8, 1933, Serial No. 697,221

8 Claims; (Cl. 123-179) started and while it is running under its own power. It is desirable to retard the spark during the cranking operation in order to prevent the engine from being driven backward, and it is desirable to advance the spark during normal running so that the combustion in the engine cylinders will be complete by the time the pistons are starting on their power strokes.

V In carrying out the invention, I provide an inductive resistance which is normally excluded from the primary winding of the spark coil, but which is automatically placed in series with said coil when the starting motor is operated to crank the invention, to create a lag in the charging and discharging of said coil, which results in retarding the spark and preventing backward rotation of the engine; but as soon as the engine is started and the circuit of the starting motor is interrupted, the resistance is cut out of the circuit of the primary winding, thereby reducing the lag and causing an advance in the spark during normal running of the engine. The coil used as an inductive resistance has, necessarily, a certain amount of ohmic resistance, and this ohmic resistance may be varied as desired, either in the construction of the coil or by placing ohmic resistance in circuit with the coil. The result of including the ohmic resistance in series with the primary winding of the spark coil is to lean the spark, causing slower combustion in the cylinders, thereby delaying the full force of the explosion until the piston is on its power stroke.

In the accompanying drawings,

Fig. 1 is a diagram illustrating the invention;

Fig. 2 is a similar View showing a modification of the circuits, and,

Fig. 3 is a diagrammatic view illustrating the invention in connection with automatic engine starting means. I

Referring to Fig. 1, the starting motor, so marked, for starting the engine, is connected by conductor I through a normally open starting switch A to the storage battery 3. This ignition system includes the usual ignition switch C, circuii; breaker D, spark coil E, and distributor F. The circuit for the primary winding e of the spark coil extends from the battery through conductors I and 2 to the ignition switch, thence through conductor 3 to an arm 4 of a switch G, which is normally held in engagement with a contact 5 by a spring 6, thence by conductor 1 to the circuit breaker and thence to the primary winding 6 of the spark coil and to ground, as shown.

When the engine is running the current flows from the battery to the primary winding of the spark coil through the circuit just traced.

A magnet H is arranged adjacent the switch arm 4 and the coil of this magnet has one terminal connected by conductor 8 to the conductor I between the starting switch and the motor, and the other terminal of the magnet coil is connected by conductor 9 to ground. When the magnet is energized it moves the switch arm from its normal position against the contact 5 into engagement with a contact II) which is connectcd by conductor I I through an inductive and ohmic resistance I2 to the circuit breaker and thence to the primary winding of the spark coil. The secondary winding e of the spark coil is connected in the usual way to ground and to the distributor arm I3.

In operation, when it is desired to start the motor, the ignition switch C is closed and then the starter switch is depressed, the latter closing the circuit through the starting motor and simultaneously closing the circuit through the coil of the magnet H. This magnet moves the arm 4 away from contact 5 and into engagement with contact Ill, thus including the impedance or inductive resistance I2 in series with the primary winding of the spark coil, causing a lag in the charging and discharging of said winding, and also of the secondary winding, and hence retarding the spark at the spark plugs of the engine to a limited extent. The coil 12 also has a certain amount of ohmic resistance, or this may be separately arranged in the conductor I! and this resistance reduces the current flow to the primary winding which has the result of producing a leaner spark at the spark plugs which in turn retards combustion in the cylinders. The result is that the explosive force is applied to the pistons after the crank pins have passed over their centers. This retardation of the spark will continue while the motor is being started; but when the motor has been started and its circuit has been opened, the magnet H, which is controlled by the starting switch will be (lie-energized and the spring 6 will move the switch arm 4 out of engagement with the contact In and into engagement with the contact 5, thereby cutting the impedance coil I2 out of circuit with the primary winding of the spark coil and thereafter, while the engine is running, current will flow directly from the battery to the switches C and G and conductor 7 to the primary winding of the spark coil. The coil [2 being no longer in circuit, the lag which this coil produced in the primary winding during starting is no longer present and hence the spark will be automatically advanced for normal running of the engine.

In Fig. 2 the elements are the same as in Fig. l, exceptthat the normally closed switch G is arranged between the circuit breaker and the primary winding of the spark coil, instead of being between the circuit breaker and ignition switch, and the impedance coil is connected in shunt to the normally closed switch, instead of to a contact on said switch. In Fig. 2, parts corresponding to similar parts in Fig. l are indicated by similar reference characters. In Fig. 2, the ignition switch is connected directly to the circuit breaker by a conductor 3 and the switch arm 4 of the normally closed switch G is connected by conductor M to the contact l of the circuit breaker. The switch-arm normally en'- gages- -aacontact l 5 which .is connected byconductor W to the primary winding of the spark coil: The impedance 0011' I2 is connected in shunt to the switch arm, as shown, one terminal of the coil being connected by conductor I5 to conductor M and the other terminal of the coil being connected by conductor I5 to conductor M The magnet H for moving the switch arm 4 is connected by conductor 8- to conductor I between thestarting switch and the starting motor as in the previously described figure.

In operation, when the'starter switch is closed to start the motor and the engine, the circuit through the coil ofmagnet H is simultaneously closed and this magnet attracts the switch arm 4 away from'thecontact l6 thereby interrupting the direct course of'the current to the coil e and causing the current to -fiow through the shunt circuit l5, 5 and impedance coil I2, thereby causing a lag in the charging and discharging of the primary winding of the spark coil, and also of the secondary winding, as described in connection with Fig. 1. The switch G remains open as long as the motor circuit is closed and the=-engine is being started; but immediately when the engine operates under its own power and the starting motor circuit is opened, either automatically or otherwise, the maget H becomes. de-energized and the switch G closes, thereby shunting the impedance coil and'reducing the lag in the charging and discharging of the windings in the spark coil and hence advancing' the-spark, during normal running of the engine.

In Fig. 3 of the drawings, I have shown the invention diagrammatically in connection with a startingsystem in which the starter motor operates to start the engine automatically when the ignition switch is closed and in which the circuit of the starter motor is interrupted automatically after the engine has started. In this arrangement, a relay magnet operates a switch which controls the motor circuit and a switch which includes the inductive resistance in series with 'the'primary winding of the spark coil while the engine is being started and cuts out this resistance as soon as the engine is operating under its own power.

InFig. 3, elements corresponding to similar elements in the previously described figures are indicated by similarreferencecharacters. The

' circuit l for the starter motor extends from the battery through a normally open starting switch A. The ignition circuit extends from the switch C by conductor I! to normally closed switch G, thence through circuit breaker D to the primary winding 6 of the spark coil E. The inductive resistance 12 is connected in shunt to the terminals l8 of the switch G. so that normally this 5 resistance is 'short-circuited, but when the switch is open, the resistance is included in series with the coil e. A circuit l9 extendsfrom the ignition switch through the coil of a relay magnet H and thence to contact 20 of a switch J, thence through a contact 2| on a switch arm 22 to switch-contact 23 and thence by conductor 24 to ground. The switch arm 22, as illustrated in the drawings, is operable by a centrifugal governor 25, suitably driven from the internal combustion engine K. The switch J is normally closed but when the engine starts, the governor moves the contact arm 22 so as to carry the contact piece 2| off of the contacts and 23, thereby opening the circuit of the relay magnet. 20

In operation, when the ignition switch is closed, the relay, magnet is energized and the bridge piece 26 is moved into engagement with the contacts 21, thereby closing the circuit of the starting motor, which cranks the engine. Simultaneouslywith the closure of the switch A, the bridge piece 29 is lifted from the contacts i8 thus opening the switch G and breaking the shunt around the inductive resistance l2 so that this resistance is included in series with the 30 primary winding" of the spark coil. Thus, while the starting motor is cranking the engine, a lag will be created by the inductive resistance in the primary winding of the spark coil, with a corresponding retardation of the induced current in the secondary winding which will cause the spark to be retarded at the spark lugs of the engine. While the engine is being cranked, the speed ofthe centrifugal governor will not be. sufficient to move the switch lever 22 away from the contacts 20'and 23; but as soon as the engine starts, the governor will move this lever to open the switch J, thus interrupting the coil of ,therelay magnet and when the magnet is de-energized, the switch' A', in the motor circuit, will open, to stop, the motor, and the switch G will close and short-circuit theinductiveresistanceL The exclusion of the inductive resist an'ce from the circuit of the primary winding of the spark. coil will cause the spark to be advanced for normal running of the engine.

I have shown, for ease of illustration, 3. centrifugal governor operated by the engine for controlling the circuit of the relay magnet; but it will be understood that any other suitable means operated by the engine may be employed for controlling this circuit.

The circuit breaker is a necessary feature of all battery ignition systems, to cause induction between the primary and secondary windings of the spark coil, and in my invention it serves the additional purpose of making and breaking the circuit through the inductance coil, ,whenlthe latter is in series with the primary winding, ,to cause the. desired lag, in the charging and discharging of the primary winding.

What I claim is:

1. The combination with a motor for starting internal combustion engines, a starting switch for the motor, and an ignition system for the engine comprising a, spark coil having a primary winding and a circuit therefor, of an inductive resistance and means for including said resistance in said circuit while the motor is starting the engine and for excluding said resistance from said circuit after the engine has been started.

2. The combination with a motor for starting internal combustion engines, a starting switch for the motor, and an ignition system for the engine comprising a spark coil having a primary winding and a circuit therefor, of an inductive resistance, normally excluded from said circuit, and means controlled by the starting switch for including said resistance in said circuit when the starting switch is closed.

3. The combination with amotor for starting internal combustion engines, a circuit for the motor, a switch for starting the motor, and an ignition system for the engine comprising a spark coil having a primary winding and a circuit for said winding, of an inductive resistance, normally excluded from the latter circuit, and means for including the resistance in circuit with said winding when the motor circuit is closed and for excluding the resistance from the circuit of said winding when the motor circuit is interrupted.

4. The combination with a motor for starting internal combustion engines, a circuit for the motor, a switch for starting the motor, and an ignition system for the engine comprising a spark coil having a'primary winding and a circuit for said winding, of an inductive resistance, a switch in the latter circuit, normally excluding the resistance therefrom and movable to include said resistance, a magnet for moving said switch to include the resistance in the latter circuit and v a circuit for the magnet controlled by said switch.

6. The combination with an internal combustion engine, a starting motor therefor, a circuit for the motor, an ignition system including a spark coil having a primary winding, a circuit for said winding and an ignition switch for closing the latter circuit, of an inductive resistance normally excluded from the latter circuit, means for automatically closing the motor circuit and for including said resistance in series with said primary winding when the ignition switch is closed and means controlled by the engine, when started, for opening the motor circuit and for excluding said resistance from the circuit of said primary winding.

'7. The combination with an internal combustion engine, a starting motor therefor, a normally open circuit for the motor, and an ignition system comprising a spark coil having a primary winding, a circuit for said winding, and an ignition switch, of an inductive resistance normally excluded from the latter circuit, a magnet having a circuit adapted to be closed by the ignition switch, switches operated by said magnet, when energized, adapted to close the motor circuit and to include said inductive resistance in circuit with said primary winding, and means operated by the engine, when started, for die-energizing the magnet.

8. The combination with an internal combustion engine, a starting motor therefor, a circuit for the motor including a normally open switch, an ignition system comprising a spark coil having a primary winding, a circuit for said winding including a normally closed switch and an ignition switch, of an inductive resistance normally excluded from the latter circuit and adapted to be included therein when the normally closed switch opens, electromagnetic means for closing said normally open switch and for opening said normally closed switch when the ignition switch is closed, and means operated by the engine, when started, for de-energizing said electromagnetic means.

JOHN RALPH PRICE. 

